Systems for forming t-shaped fins from metal rods



' Dec. 10, 1968 A. STIKELEATHER ET AL 3,415,094

' SYSTEMS FOR FORMING T-SHAPED FINS FROM METAL RODS Filed Nov. 16, 1966 5 Sheets-Sheet 1 as 2| 8? 92 ijzo INVENTORS ALAN STIKELEATHER X, ROBERT M.ST|KELEATHER BYWLjM ATTORNEY FIG.4.,I I 26 Dec. 10, 196-8 A. STIKELEATHER ET 3,415,094

SYSTEMS FOR FORMING T-SHAPED mus FROM METAL RODS Filed Nov. 16, 1956 s sheets-sheet 2 I I I i m m g INVENTORS ALAN STIKELEATHER & ROBERT M. STIKELEATHER,

' BYW0- ATTORNEY.

Dec. 10, 1968 A, STIKELEATHER ET AL 3,415,094;

SYSTEMS FOR FORMING u smmn FINS FROM METAL RODS Filed Nov. 16, 1966 5 Sheets-Sheet :5

INVENTORS ALAN STIKELEATHERzfi ROBERT M.STIKELEATHER,

1 BYWJWY QM ATTORNIEY FIG.8.

Dec; 10,1968 A. STIKELEATHER EYTAL 3,415,094

SYSTEMS FOR FORMING T-SHAPED FINS FROMMETAL RODS Filed Nov. 16, 1966 5 Sheets-Sheet 4 INVENTORS ALAN smznmwm& ROBERT MQSTIKELEATHER,

.BY W \7 v ATTORNEY Dec. '10, 1968 A. STIKELEATHER 3,415,094

$YSTEMS FOR FORMING T-SHAPED FINS FROM METAL Roms Filed Nov. 16, 1966 5, Sheets-Sheet 5 I 'INVENTORS ALAN sTIKELEA-THER & ROBERT M. STIKELEATHER,

T BYMQ.

ATTORNEY United States Patent 3,415,094 SYSTEMS FOR FORMING T-SHAPED FINS FROM METAL RODS Alan Stikeleather, Green Lodge St, Canton, Mass. 02021, and Robert M. Stikeleather, 324 N. Franklin St., Holbrook, Mass. 02343 Filed Nov. 16, 1966, Ser. No. 594,750 6 Claims. (Cl. 72187) ABSTRACT OF THE DISCLOSURE For forming a T-shaped fin, a metal rod is passed between a first pair of driven rolls, one of which has a rippled surface, and the other one of which has a cylindrical surface. These rolls form a rippled surface on the rod which meshes with the rippled surface on the one of the rolls in gear-like action, and forces the rod through following pairs of rolls. The rippled rod then passes between second through seventh pairs of driven rolls which progressively deform the rod to a T-shaped ribbon. The ribbon then passes through a burr removing station.

This invention relates to the formation of generally T-shaped, heat exchange fins from metal rods.

The US. Patents Nos. 2,713,375 and 2,799,389 disclose how metal ribbon can be caused to curl about and adhere to heat exchange tubes for forming so-called fins on such tubes. For some duties, it is desirable to be able to preform the ribbon to have a generally T-shape, so that when the ribbon is Wound on a tube, the cross of the T forms the base of the fin in contact with the surface of the tube. This invention forms such a T-shaped fin from a rod of metal such as aluminum or copper.

In one embodiment of this invention, a rod of metal, circular in section, is passed in a first station between a pair of driven rolls, one of which has a rippled surface, and the other of which has a cylindrical surface. These rolls flatten the rod somewhat, but what is more important, the rippled surface of the one roll forms in the rod, corresponding ripples which act, in effect, as gear teeth, meshing with the ripples on the one roll to prevent slippage and cause a constant rate of rod feed to the following stations which change its shape to that of a T. The first station is followed by stations two through eight. The stations two through four contain pairs of driven rolls which gradually change the shape of the rod to approach the desired T-shape. The fifth and sixth stations contain pairs of driven rolls which thin the portion of the rod which forms the leg of the fin, and also contain pairs of rolls with axes normal to those of the other rolls, which thin the portion of the rod which forms the base of the fin. The seventh station is generally similar to the fifth and sixth stations except that it has roll surfaces added to the driven rolls for limiting the width of the base of the fin. The eighth station contains knife edges for removing burrs from the sides and the bottom of the base of the fin.

An object of this invention is to form a generally T-shaped fin from a metal rod.

This invention will now be described with reference to the annexed drawings, of which:

3,415,094 Patented .Dec. 10, 1968 FIG. 1 is a diagrammatic plan view of a fin forming system embodying this invention;

FIG. 2 is a side view, artially in section, of the rolls of the first station, with fragmentary views of their shafts, and of the meshing gears on their shafts;

FIG. 3 is a fragmentary view along the lines 3-3 of FIG. 2;

FIG. 4 is a side view, partially in section, of the rolls of the second station, with fragmentary views of their shafts, and of the meshing gears on their shafts;

FIG. 5 is a fragmentary section showing how the rolls of FIG. 4 are modified to form the rolls of the third station;

FIG. 6 is a fragmentary section showing how the rolls of FIG. 4 are modified to form the rolls of the fourth station;

FIG. 7 is a side view, partially in section, of the rolls of the fifth station, with fragmentary views of the shafts of the seventh station, with fragmentary views of the shafts, the rolls of the sixth station being similar except that their rod contacting surfaces are closer together;

FIG. 8 is a side view, partially in section, of the rolls of the seventh station, with fragmentary views of the shafts of the driven rolls, and of the meshing gears on such shafts;

FIG. 9 is a side view of the eighth station;

FIG. 10 is a plan view of FIG. 9;

FIG. 11 is a view of FIG. 9 at its outlet end;

FIG. 12 is a view along the lines 1212 of FIG. 10; and

FIG. 13 is a view along the lines 1313 of FIG. 10.

Referring first to FIG. 1, an electric motor M, drives through pulleys 20 and 21 and belt 22, a. conventional gear box 23 which drives through pulleys 24 and 25, belt 26, shaft 27, pulleys 28 and 29, belt 30, shaft 31, pulleys 32 and 33, belt 34, shaft 35, pulley 36, belt 38, and pulley 37 on one end of shaft 39 of box A of the first station, the shaft 39. The gear box 23 drives through. pulleys 53 and 54, belt 55, shaft 56, pulley 57 and belt 58, pulley 59 on shaft 60 near one end of the latter, of box F of the sixth station. The shaft 60 drives through pulley 61 on one end of the shaft 60, belt 62 and pulley 63 on one end of shaft 64 of box E of the fifth station. Pulley 65 on the shaft 64 drives through belt 66, pulley 67 on shaft 68 near one end of the latter, of box D of the fourth station. Pulley 70 on one end of the shaft 68 drives through belt 71, pulley 72 on one end of shaft 73 of box C of the third station. Pulley 74 on the shaft 73 drives through belt 75, pulley 76 on one end of the shaft 77 of box B of the second station. The gear box 23 drives through pulleys 77 and 78, and belt 79, shaft 80 which drives through pulley 81 and belt 82, pulley 83 on one end of shaft 84 of box G of the seventh station.

The boxes A, B, C, D, E, F and G contain conventional bearings, housings, and supports which are not shown. The other end of the shaft 39 of the box A of the first station has upper roll 85 attached thereto. The other end of the shaft 77 of the box B of the second station, has upper roll 86 attached thereto. The other end of the shaft 73 of the box C of the third station, has upper roll 87 attached thereto. The other end of the shaft 68 of the box D of the fourth station, has upper roll 88 attached thereto. The other end of the shaft 64 of the box E of the fifth station, has upper roll 89 attached thereto. The other end of the shaft of the box F of the sixth station, has upper roll 90 attached thereto. The other end of the shaft 84 of the box G of the seventh station, has upper roll 91 attached thereto. The line 92 passing under the transverse centers of the rolls 85-91 represents the T-shaped fin being formed.

Referring now to FIGS. 2 and 3, roll 85 of the box A is attached to the shaft 39 by being clamped between similar circular spacers 95 and 96 which are clamped between enlargement 97 of the shaft 39, and cap 98 by a stud 99. The shaft 39 has a gear 100 attached thereto which meshes with a similar gear 101 on a shaft 102 below and aligned with the shaft 39. A roll 103 aligned with the roll 85 is attached to the shaft 102 by being clamped between similar flange rolls 105 and 106 which are clamped between enlargement 107 of the shaft 102 and cap 108 by stud 109. The flange rolls 105 and 106 are aligned with the spacers 95 and 96 respectively, but have larger diameters than the latter so that they extend upwardly beyond the lower portion of the roll 85, forming an enclosed space between the rolls 85 and 103 through which the rod being deformed travels.

The roll 85 has a rippled surface 110 opposite and spaced from cylindrical surface 111 of the roll 103. A circular rod 112 passing between the rolls 85 and 103 is compressed, and its upper surface is deformed to have ripples 113 which act in effect, as gear teeth meshing with the ripples in the surface 110 of the roll 85 so that the rod has a constant rate of feed to the following stations.

Referring to FIG. 4, the roll 86 of the box B of the second station, is attached to the shaft 77 by being clamped between similar spacers 114 and 115 which are clamped between enlargement 116 of the shaft 77, and cap 117 by stud 118 threaded into the shaft 77. The roll 86 has a cylindrical surface 120, and a cylindrical surface 121 having a slightly smaller diameter than that of the surface 120. The shaft 77 has a gear 122 attached thereto, which meshes with a similar gear 123 on shaft 124 below and aligned with the shaft 77. A roll 125 below and aligned with the roll 86 is attached to the shaft 124 by being clamped between similar flange rolls 126 and 127 which are clamped between enlargement 128 of the shaft 124 and cap 129 by stud 130 threaded into the shaft 124. The flange rolls 126 and 127 are below and aligned with the spacers 114 and 115 respectively. The rolls 126 and 127 have larger diameters than the plates 114 and 115, and extend upwardly beyond the bottoms of the latter, on

opposite sides of and closely adjacent to the aligned inner and outer surfaces of the rolls 86 and 125. The roll 125 has a cylindrical surface 132 opposite and aligned with the surface 120 of the roll 86, and has a cylindrical surface 133 having a slightly smaller diameter than that of the surface 132, aligned with the surface 121 of the roll 86. The roll surfaces 120 and 132 deform the rod 112 to start the formation of the leg of the fin, and the roll surfaces 121 and 133 start the formation of the base of the fin. The flange rolls 126 and 127 prevent the rod 112 from being forced outwardly from between the rolls 86 and 125. Referring now to FIG. 5, the rolls of the box C of the third station are similar to those of the second station shown by FIG. 4 except that roll 87 corresponding to the roll 86 of FIG. 4, and roll 125A corresponding to the roll 125 of FIG. 4, instead of having rod deforming surfaces with diflerent diameters, have cylindrical surfaces 139 extending across their widths, and which thin the base only of the fin being formed, squaring the base so that it can fill up the space between the base deforming rolls of box D of the fourth station, shown by FIG. 6.

Referring now to FIG. 6, the rolls of the fourth station are similar to those of the second station shown by FIG. 4, except that the roll 88 corresponding to the roll 86 of FIG. 4, and roll 125B corresponding to the roll 125 of FIG. 4, have rod deforming surfaces spaced closer together.

Referring now to FIG. 7, the roll 89 of the box E of the fifth station, is attached to the shaft 64 by being clamped between spacer 135 and cap 136, with the spacer 135 being clamped against enlargement 137 of the shaft 64, by stud 138 threaded in the shaft 64. The shaft 64 has a gear 140 attached thereto, which meshes with a similar gear 141 attached to a shaft 142 below and aligned with the shaft 64. A roll 143 below and aligned with the roll 89 is attached to the shaft 142 by being clamped between flange roll 144 and cap 145, with the flange roll 144 clamped against enlargement 146 of the shaft 142, by stud 147 threaded in the shaft 142. The rolls 89 and 143 have spaced-apart, aligned, cylindrical rod deforming surfaces 150 and 151 respectively, which act to thin and lengthen the leg of the fin being formed. The flange roll 144 has a larger diameter than the plate 135, and its upper portion extends above the rod deforming surfaces 150 and 151 where they approach each other, and closely adjacent to the inner (right) surfaces of the rolls 89 and 143. An idler roll 152 having a vertical shaft 153 attached to the frame 154, has a vertical, cylindrical surface 155 spaced outwardly from the outer (left) surfaces of the rolls 89 and 143, and deforms the rod to thin the base of the fin being formed. The flange roll 144 backs up the rolls 89 and 143, opposing the pressure from the roll 152.

The box F of the sixth station has rolls constructed the same as the rolls shown by FIG. 7, except that the rod deforming surfaces are closer together. The roll 90 of the box F corresponds to the roll 89 of the box E shown by FIG. 7.

Referring now to FIG. 8, the roll 91 of the box G of the seventh station is attached to the shaft 82 by being clamped between spacer 155 and roll 156, the spacer 155 being clamped against enlargement 157 of the shaft 82 by cap 158 and stud 159 threaded in the shaft 82. The shaft 82 has a gear 160 attached thereto and which meshes with a similar gear 161 attached to shaft 162 below and aligned with the shaft 82. A roll 163 is attached to the shaft 162 by being clamped between flange roll 164 and roll 165, the roll 164 being clamped against enlargement 186 of the shaft 162 by cap 167 and stud 168 threaded in the shaft 162. The rolls 91 and 163 have cylindrical surfaces which contact at 168, and have spaced-apart, cylindrical surfaces 169 and 170 respectively, having smaller diameters than the surfaces which contact at 168. The roll 164 has a larger diameter than the spacer 155, and its upper portion extends above the contacting surfaces of the rolls 163 and 191. The rolls 156 and have spacedapart surfaces 172 and 173 respectively, which have smaller diameters than the surfaces 169 and respectively. An idler roll 175 is attached by screws 176 to roll 177 which has a vertical shaft 178 supported from frame 179. The roll 175 has a vertical cylindrical surface 180 spaced outwardly from the outer (left) surfaces of the rolls 91 and 163, and having a width larger than the distance between the surfaces 169 and 170. The roll surfaces 169 and 170 complete the thinning of the leg of the fin. The roll surfaces 172 and 173 complete the reduction of the width of the base of the fin. The roll surface 180 and the adjacent outer side surfaces of the rolls 91 and 163 complete the reduction of the thickness of the base of the fin. Thrust bearings on shaft 82 and 162 back up rolls 91 and 163 against pressure from the roll surface 180.

FIGS. 913 show the construction of the eighth station in which burrs are removed from the bottom and side edges of the base of the formed fin. A resilient strap 182 of spring metal is attached at one end by screws 183 and plate 184 to extension 185 of frame 186, and is attached at its other end by screws 187 to vertically extending portion 188 of one end of bracket 189. The bracket 189 has a vertically extending portion 190 at its other end, to which is attached by screws 191, a scraper plate 192 having a knife edge 193. Attached by screws 194 to the bracket portion 190 is a scraper plate 195 having a slot 196 therein with opposite sharp edges 197. Attached to the frame 186 by a screw 199 is a plate 200 having a downwardly extending portion 201 with a flat, horizontally extending bottom surface. Attached to the frame 186 by a screw 203 is a plate 204 having an upwardly extending portion 205 having a flat top surface parallel to the bottom surface of the plate portion 201.

A T-shaped fin having a leg 208 and a base 209 adva'nces from the seventh station shown by FIG. 8, and passes with the top surface of its leg 208 in contact with the bottom surface of the plate portion 201, and with the bottom surface of its leg 208 in contact with the bottom surface of the plate portion 205, such plate surfaces being spaced apart the thickness of the leg 208, and acting as a guide for the fin, and holding it in place for the following operations. The fin next passes the plate 192 with the bottom of its base 209 in contact with the knife edges 193 of the plate 192, which removes burrs formed during the preceding rolling operations from the bottom surface of the base 209. The fin finally passes through the slot 196 in the plate 195, with the ends of its base 209 in contact with the knife edges 197 which remove burrs resulting from the preceding rolling steps.

The resiliency of the spring strap 182 attached to the plate 189, causes the bottom surface of the base 209 of the fin to contact the knife edges 193 with the proper pressure to cause removal of burrs without damaging the bottom surface of the base 209.

It is desirable to remove the burrs from the bottom surface of the base of the fin so as to permit the base to be wound in close contact with the surface of a tube, and it is desirable to remove the burrs from the end surfaces of the base so that the end surfaces of the bases of adjacent turns of the fin can be in close contact as the fin is wound on a tube.

In operation, a metal rod is started by hand in between the rod deforming surfaces of the rolls 85 and 103 of the first station shown by FIG. 1. The rod is flattened, and its upper surface is rippled as shown by FIG. 2, so that it can act effectively as a gear meshed with the rippled surface of the roll 85, to cause the rod to move at a uniform rate to the following stations.

In stations two and four, shown by FIGS. 4 and 6 respectively, the rod deforming roll surfaces decrease the width of the base and leg of the fin. In station three, shown by FIG. 5, the rod deforming roll surfaces decrease the width of the base only of the fin. In the stations two through four, retaining rolls alongside the rod deforming rolls, prevent the rod being deformed from bulging out from between the rod deforming surfaces.

In stations five and six, shown by FIG. 7, the thickness of the base and of the leg of the fin are reduced.

In station seven, shown by FIG. 8, the reductions in the thickness and width of the base of the fin, and the reduction in thickness of the leg of the fin, are completed.

In station eight shown by FIGS. 9-13, the burrs formed on the bottom and end surfaces of the base of the fin, are removed so that the base can be wound spirally on a tube in close contact therewith, with the end surfaces of the bases of adjacent turns of the fin in close contact.

What is claimed is:

1. A system for forming a generally T-shaped ribbon from a metal rod, comprising:

a first pair of aligned, driven rolls having parallel axes, and having spaced-apart, rod deforming surfaces, one of said surfaces being cylindrical, and the other one of said surfaces being rippled;

a second pair of aligned, driven rolls having axes parallel to said axes, and each having a first and a second rod ,deforming surface, said first surfaces being aligned, said second surfaces being aligned, said second surfaces being spaced apart, said first surfaces being spaced apart further than said second surfaces;

a pair of retaining rolls having an axis on the axis of one of said rolls of said second pair, and having inner surfaces extending closely adjacent to the outer surfaces of said rolls of said second pair towards said axis of the other roll of said second pair beyond where said first surfaces are closest; and

means for driving said rolls.

2. A system as claimed in claim 1 in which there are provided:

a third pair of aligned, driven rolls having axes parallel to said axes, and having cylindrical rod deforming surfaces spaced apart closer than said first surfaces, and further than said second surfaces;

a second pair of retaining rolls having an axis on the axis of one of said rolls of said third pair, and having inner surfaces extending closely adjacent to the outer surfaces of said rolls of said third pair, towards said axis of the other roll of said third pair beyond where said cylindrical surfaces of said rolls of said third pair are closest; and

means for driving said rolls of said third pair.

3. A system as claimed in claim 2 in which there are provided:

a fourth pair of aligned, driven rolls having axes parallel to said axes, and each having a first and a second roll deforming surface, said first surfaces of said rolls of said fourth pair being aligned, said second surfaces of said rolls of said fourth pair being aligned, said second surfaces of said rolls of said fourth pair being spaced apart closer than said second surfaces of said rolls of said second pair, said first surfaces of said rolls of said fourth pair being spaced apart closer than said first surfaces of said rolls of said second pair and further than said second surfaces of said rolls of said fourth pair;

a third pair of retaining rolls having axes on the axis of one of said rolls of said fourth pair, and having inner surfaces extending closely adjacent to the outer surfaces of the rolls of said fourth pair towards said axis of the other roll of said fourth pair beyond where said first surfaces of said rolls of said fourth pair are closest;

and means for driving said rolls of said fourth pair.

4. A system as claimed in claim 3 in which there are provided;

a fifth pair of aligned, driven rolls having axes parallel to said axes, and having cylindrical rod deforming surfaces spaced apart closer than said second surfaces of said rolls of said fourth pair; means for driving said rolls of said fifth pair;

an idler roll having an axis normal to said axes of said rolls of said fifth pair, and having a cylindrical surface spaced from and adjacent to the outer surfaces of said rolls of said fifth pair where said cylindrical surfaces of said rolls of said fifth pair are closest; and

a backing-up roll having an axis on the axis of one of said rolls of said fifth pair, and having an outer surface extending closely adjacent to the inner surfaces of said rolls of said fifth pair towards said axis of the other roll of said fifth pair beyond where said cylindrical surfaces of said rolls of said fifth pair are closest.

5. A system as claimed in claim 4 in which there are provided:

a sixth pair of aligned, driven rolls having axes parallel to said axes of said driven rolls, and having first contacting surfaces, and second, spaced-apart, cylindrical rod deforming surfaces spaced closer together than said cylindrical surfaces of said rolls of said fifth pair;

a seventh pair of aligned, driven rolls, having axes on said axes of said rolls of said sixth pair, and driven with said rolls of said sixth pair, said rolls of said seventh pair having inner surfaces in contact with the having aligned, spaced apart, cylindrical rod deforming surfaces spaced further apart than said cylindrical surfaces of said rolls of said sixth pair;

a second idler roll having an axis normal to said axes of said rolls of said seventh pair, and having a cylindrical rod deforming surface extending between said cylindrical surfaces of said rolls of said seventh pair; and

means for driving said rolls of said sixth and seventh pairs.

6. A system as claimed in claim 5 in which there are provided:

means for scraping burrs from that surface of the deformed rod which contacted said cylindrical surface of said second idler roll; and

means for scraping bu-rrs from those surfaces of the deformed rod which contacted said cylindrical surfaces of said rolls of said seventh pair.

References Cited UNITED STATES PATENTS 10 CHARLES W. LANHAM, Primary Examiner.

L. A. LARSON, Assistant Examiner.

US. Cl. X.R. 

